81013111 has 2 divisors, whose sum is σ = 81013112. Its totient is φ = 81013110.

The previous prime is 81013103. The next prime is 81013123. The reversal of 81013111 is 11131018.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 81013111 - 2³ = 81013103 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (81013181) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40506555 + 40506556.

It is an arithmetic number, because the mean of its divisors is an integer number (40506556).

Almost surely, 2^81013111 is an apocalyptic number.

81013111 is a deficient number, since it is larger than the sum of its proper divisors (1).

81013111 is an equidigital number, since it uses as much as digits as its factorization.

81013111 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 24, while the sum is 16.

The square root of 81013111 is about 9000.7283594163. The cubic root of 81013111 is about 432.6982146897.

Adding to 81013111 its reverse (11131018), we get a palindrome (92144129).

The spelling of 81013111 in words is "eighty-one million, thirteen thousand, one hundred eleven".